Filters in Essbase BSO

Hi Gurus,

Scenario: We got a budget cube with Y2018 Lock and send data and created a new member Y2019 for new uploads. Key requirement is while uploading new years budgets need to keep a filter on Y2018 so that no one post accidentally on Y2018.

I have created a filter called Y2018 and assigned Read access.

but assign tab is grayed out any idea? is there any better option to achieve this. I thought of creating new DB for 2019 but both 2018 and 2019 data has to migrate using ODi to Pivot Stream(PS) every now then.

I have ODI setup already on 2018 so just adding 2019 would be just adding Y2019 in calc script would  export 2 yrs data in to PS.